The ruling upholding the tighter limits on soot, or fine particulate matter (PM2.5), by the U.S. Court of Appeals for the D.C. Circuit dismissed arguments from the National Association of Manufacturers, U.S. Chamber of Commerce and other industry groups that challenged EPA’s methods of weighing the science, its response to industry comments on the proposal, the timing of an implementation rule and its monitoring requirements.

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In addition to the opposition from industry groups to lowering the soot standard from 15 micrograms per cubic meter to 12, the rulemaking caused controversy in Congress, where some lawmakers said they feared the EPA was preparing to regulate dust from farms, too. Soot is largely produced by automobiles and power plants.

The ruling, which comes after Judges Janice Rogers Brown, David Tatel and Brett Kavanaugh showed no sign of being swayed by industry arguments at oral arguments in February, is the latest appeals court decision upholding the agency’s efforts to tighten human health-based air quality standards for several pollutants.

In 2012, the same court upheld EPA’s tightened “primary” standards for sulfur dioxide and nitrogen dioxide, and it later upheld the agency’s 2008 ozone air-quality standard.

“Time after time, courts have found that EPA’s clean air standards are solidly based in science and the law,” said Environmental Defense Fund attorney Peter Zalzal. “Soot is an extremely dangerous and sometimes deadly pollutant that causes heart attacks and asthma attacks.”

National Association of Manufacturers general counsel Linda Kelly criticized the ruling, saying it would add to the numerous regulations already facing manufacturers.

“The court’s decision also underscores the difficulty manufacturers face in pushing back against a powerful and often overreaching EPA. The Manufacturers’ Center for Legal Action is reviewing the decision and considering future options,” she said in a statement.

In upholding the EPA standards, the court again granted “deference” to EPA to make judgments in complicated scientific decisions. That deference was also seen in the Supreme Court’s recent ruling upholding EPA’s Cross-State Air Pollution Rule, and in prior appeals court rulings on climate change regulations and emissions standards at lead-smelting facilities.

Friday’s opinion, penned by Kavanaugh, shot down one argument after another from the rule’s opponents, including the contention that EPA should have first requested comment on whether to revise the standard at all before it put the details of its proposal up for public comment.

“Although it is true that EPA did not specifically ask for comments on whether revision was necessary,” the agency did say it wanted to hear comment on “all issues” related to the proposal, Kavanaugh wrote. Anyone could have commented on whether any revision was warranted, and some did just that, he wrote in the opinion. “EPA’s notice sufficed.”

The groups also challenged EPA’s review of the scientific evidence, saying the agency gave disproportionate weight to some studies over others.

The Clean Air Act requires EPA to review the standards every five years to determine whether the science is up to date. The Supreme Court has previously ruled that the standards must be set at a level that is safe, without consideration of what it costs to get there.

“Here, we can be brief,” Kavanaugh wrote. The groups “simply have not identified any way in which EPA jumped the rails of reasonableness in examining the science. EPA offered reasoned explanations for how it approached and weighed the evidence, and why the scientific evidence supported revision of the [standard].”

The court also ruled it isn’t necessary for EPA to respond directly to each comment on the rule and that EPA’s decision to remove “spatial averaging” was within the agency’s rights.

The groups also argued that EPA should have better explained why it made the change, but the opinion said the court doesn’t “assign ‘presumptive validity’” to prior rules — “the question is whether EPA reasonably explains the current standards,” the ruling said.

The court also found EPA’s explanation for requiring 50 new air-quality monitors near heavily traveled roads in major metropolitan areas to be “at least reasonable.”

While the rule’s opponents said the monitors would shift the weight of survey results, EPA argued they would more accurately measure the air that many people breathe in real-world conditions.

The court also ruled that EPA did not have to provide implementation guidance at the same time that it issued the rule. The standard “sets a clear numerical target specifying the maximum levels of emissions in the states,” the opinion said. “Nothing in the law dictates additional guidance from EPA at this point,” it said.